Documentation has some issues problems and needs more people to fix it.
One of the problems is how to test the documentation before doing a merge request.
I have created a docker image that makes it easy. Just install docker and run:
docker run -d -it -p 8080:80 --name grav -v $HOME/the/place/you/have/documentation:/usr/share/nginx/html/user/pages elmanytas/ahumaro-grav-hifi
Then go to http://localhost:8080
Here is the webpage: https://hub.docker.com/r/elmanytas/ahumaro-grav-hifi/